生物技术通报 ›› 2018, Vol. 34 ›› Issue (1): 144-152.doi: 10.13560/j.cnki.biotech.bull.1985.2017-0652

• 研究报告 • 上一篇    下一篇

茶树1-脱氧-D-木酮糖-5-磷酸合成酶基因CsDXS1的克隆与表达分析

郭亚飞, 王君雅, 郭飞, 倪德江   

  1. 华中农业大学园艺林学学院 园艺植物生物学教育部重点实验室,武汉 430070
  • 收稿日期:2017-08-07 出版日期:2018-01-26 发布日期:2018-01-22
  • 作者简介:郭亚飞,男,硕士研究生,研究方向:茶树次生代谢与调控;E-mail:1993842107@qq.com
  • 基金资助:
    国家自然科学基金项目(31600556),中央高校基本科研业务费专项(2662015BQ035)

Cloning and Expression Analysis of CsDXS1 Gene Encoding 1-Deoxy-D-Xylulose-5-Phosphate Synthase in Camellia sinensis

GUO Ya-fei, WANG Jun-ya, GUO Fei, NI De-jiang   

  1. Key Laboratory of Horticultural Plant Biology,Ministry of Education,College of Horticulture and Forestry Sciences,Huazhong Agricultural University,Wuhan 430070
  • Received:2017-08-07 Published:2018-01-26 Online:2018-01-22

摘要: 1-脱氧-D-木酮糖-5-磷酸合成酶(1-deoxy-D-xylulose 5-phosphate synthase,DXS)是MEP 萜类合成途径的第一个关键酶,在植物萜类物质的生物合成过程中发挥重要的作用。以福鼎大白茶为实验材料,在课题组前期转录组数据的基础上,运用 RT-PCR 技术克隆了茶树CsDXS1基因的完整开放阅读框(ORF)。该 ORF长度为 2 154 bp,编码717个氨基酸。生物信息学分析结果表明,茶树CsDXS1蛋白与其他植物的同源蛋白相似性高达85%-90%,属于 DXS基因家族的I类基因,该蛋白是不稳定的亲水蛋白,不存在信号肽和跨膜结构域,有15个可信度高的磷酸化位点,具有典型的转酮醇酶亚家族功能域。利用实时荧光定量 PCR 对 CsDXS1基因在茶树不同组织和不同激素处理下的表达谱进行检测,结果显示:不同组织中,CsDXS1基因的表达水平在第三叶中最高,嫩叶中的表达量显著高于茎和老叶,表达水平从高到低依次为第三叶>第四叶>第二叶>第一叶>嫩茎>老茎>老叶。在不同激素处理中,CsDXS1的表达量受到不同程度的诱导,且表达量峰值的出现时间存在差异。CsDXS1在IAA和ABA激素处理下的表达量峰值最高(4 h),均为对照的1.5倍,在 MeJA 处理下表达量峰值最低(24 h),仅为对照的1.1倍。

关键词: 茶树, 1-脱氧-D-木酮糖-5-磷酸合成酶, 萜类化合物, 序列分析, 表达分析

Abstract: 1-deoxy-D-xylulose-5-phosphate synthase(DXS)is the first key enzyme of the MEP terpenoids synthetic pathway,thus it plays an important role in the biosynthesis of plant terpenoid. In this study,the complete ORF of CsDXS1 gene was cloned from Camellia sinensis var. fudingdabaicha based on the previous tea plant transcriptome database,and it’s length was 2 154 bp encoding 717 amino acids. The bioinformatics analysis indicated that CsDXS1 gene belonged to the class I of DXS gene family. The deduced CsDXS1 protein shared high similarity(85%-90%)with other homologous protein,and it was an instable and hydrophilic protein with no signal peptide and transmembrane domain. There were 15 high-probability phosphorylation sites. Furthermore,CsDXS1 had two typical conserved domains of transketolase superfamily. The expression profiles of CsDXS1 gene in different tissues of tea plant or under hormonal treatments were detected using quantitative real-time PCR analysis. Results showed that CsDXS1 exhibited the highest expression in the third leaf,and higher expressions in the young leaves than in the steam and old leaves. The tissue expression profiles showed that the successive order as the third leaf > the fourth leaf > the first leaf > the second leaf > young stem > old stem >old leaf. The CsDXS1 gene expression were induced at varied degrees in response to six hormonal treatments,also the occurrence times of expression peak differed. The expressions of CsDXS1 gene was in the peak(4 h)under IAA and ABA treatments,which was 1.5 times of the control. CsDXS1 gene was at the lowest expression(24 h)under MeJA treatment,which was only 1.1 times of the control.

Key words: Camellia sinensis, DXS,terpenoids, sequence analysis, gene expression